Film and cameras that are all in one, commonly referred to as one-time-use or single-use cameras, have recently become well known. Typically, the one-time-use camera is a simple point-and-shoot type comprising a plastic main body portion which supports a fixed-focus taking lens, a film metering mechanism, a manual film advance thumbwheel, a single-blade shutter, a manual shutter release button, a frame counter for indicating the number of exposures remaining for picture-taking, and a direct see-through viewfinder. Front and rear plastic cover portions house the main body portion between them to form a light-tight camera unit. A decorative cardboard outer box contains the camera unit and has respective openings for the taking lens, the shutter release button, the film advance thumbwheel, the viewfinder, and the frame counter.
At the manufacturer, the main body portion is loaded with a conventional 12, 24, or 36 exposure 35 mm film cartridge and the front and rear cover portions are connected to each other and/or to the main body portion to assemble the light-tight camera unit. Then, an exposed end of a supply spool in the main body portion is rotated to factory prewind substantially the entire length of the unexposed filmstrip from the cartridge onto the supply spool. Lastly, the outer box is placed on the camera unit.
During picture-taking, after the photographer takes a picture, he or she manually rotates the thumbwheel in engagement with a take-up spool inside the cartridge to rewind the exposed frame into the cartridge. The rewinding movement of the filmstrip the equivalent of slightly more than one frame width rotates a metering sprocket in engagement with the filmstrip, to decrement the frame counter to its next lower-numbered setting and to pivot a metering lever into engagement with the thumbwheel to prevent further manual rotation of the thumbwheel. Manually depressing the shutter release button to take a picture pivots the metering lever out of engagement with the thumbwheel. When the maximum number of exposures available on the filmstrip are exposed and the filmstrip is completely rewound into the cartridge, the one-time-use camera is given to a photofinisher who tears the outer box off the camera unit, separates the rear cover portion from the main body portion, and removes the cartridge with the filmstrip from the main body portion. Then, he removes the filmstrip from the cartridge to develop the negatives and make prints for the customer, and he forwards the used camera parts to the manufacturer for recycling, i.e. remanufacture.
Fairly recently, one-time-use cameras have been proposed which are encased in a transparent watertight housing for picture-taking underwater. A manually rotatable film winding knob is located on the watertight casing and is rotationally coupled to the thumbwheel in order to rotate the thumbwheel, as in prior art U.S. Pat. No. 5,239,324, issued Aug. 24, 1993. The film winding knob is relatively large to permit it to be readily gripped and rotated underwater. This gives rise to the possibility that one might rotate the film winding knob even though the metering lever is positioned in engagement with the thumbwheel to prevent rotation of the thumbwheel. Consequently, the film metering mechanism may be broken. To prevent this problem, Japan Kokai NO. 7-168265, published Jul. 4, 1995, suggests including a toothed face clutch between the film winding knob and the thumbwheel.
Separately, in Japan Kokai No. 7-168265, a flexible shutter release button is located on the watertight housing which is to be manually depressed to in turn depress the camera shutter release button.